KR20200089463A - High efficiency carbon dioxide power system and its start-up method - Google Patents

Abstract

The present invention relates to a supercritical carbon dioxide power generation system and a start-up method thereof and to a carbon dioxide power generation system, repeating processes of compression, heating, expansion and cooling while carbon dioxide passes through a compressor (110), a recuperator (120), a first heater (130), a turbine (140), the recuperator (120) and a cooler (150), which performs: a first step of determining whether an entrance state of the compressor is in a gas state and if the entrance state of the compressor is in the gas state as a result of the determination, driving the compressor in order to prevent an entrance operation point of the compressor from going into a vapor dome; and a second step of, if the entrance state of the compressor is not in the gas state, setting the entrance state of the compressor in a liquid state (1) on a T-S diagram and then driving the compressor. The present invention prevents the entrance operation point of the compressor from going into the vapor dome when the compressor starts up to prevent damage to the compressor and also to enhance efficiency of a carbon dioxide power generation cycle.

Description

Supercritical carbon dioxide power generation system and its starting method{HIGH EFFICIENCY CARBON DIOXIDE POWER SYSTEM AND ITS START-UP METHOD}

The present invention relates to a supercritical carbon dioxide power generation system and a method for starting the same, and more particularly, to a supercritical carbon dioxide power generation system capable of increasing the efficiency of the supercritical carbon dioxide power generation cycle and a method for starting the same.

The supercritical carbon dioxide power generation system of FIG. 1 is located on the top of a vapor dome in the T-S diagram. The vertex where the saturated liquid line meets the saturated vapor line is a critical point, and an acid-like area surrounded by the saturated liquid line and the saturated steam line is called a steam dome. At the top of the steam dome, the left side becomes the liquid region (compressed liquid) (Liquid region), and the right side becomes the gas region (superheated steam) (Vapor region), and the region inside the steam dome forms a two-phase region where liquid and vapor coexist.

The supercritical carbon dioxide generation cycle, which generally takes the form of a Brayton cycle, is compressed (1→2), heated (2→3→4), expanded (4→5), cooled (5→6→1) The process is repeated, all of which is done above the critical point of carbon dioxide (30.978℃, 7.3733MPa).

The supercritical carbon dioxide cycle of FIG. 1 changes from the liquid phase to the supercritical phase as the carbon dioxide is compressed, but the density change is smaller than the change from the liquid phase to the gas phase, so that the impact on the compressor is small and stable operation is possible. However, when starting the compressor, the temperature and pressure are not high enough, so there is a possibility that the operating point will enter the steam dome. When the operating point of the compressor enters into the steam dome, gas and liquid are mixed to increase the density change and the impact on the compressor increases, which can cause damage to the compressor.

An object of the present invention is to use a compressor to increase the efficiency of the supercritical carbon dioxide power generation cycle, and to prevent damage to the compressor, a supercritical carbon dioxide power generation system and a starting method for preventing the compressor inlet from entering the steam dome are prevented. Is to provide.

According to the features of the present invention for achieving the above object, the present invention compresses the liquid carbon dioxide at the operating point 1'of the TS diagram to become a supercritical state (2') and the compressed carbon dioxide in the compressor A recuperator heating through heat exchange and a first heater heating carbon dioxide heated in the recuperator and carbon dioxide heated in the first heater flows in and expands to produce power by being discharged from the turbine and the turbine, and the recuperator It includes a cooler to cool the incoming carbon dioxide to become the 1'liquid carbon dioxide.

And a first valve for controlling recirculation of carbon dioxide from the compressor to the cooler and a second valve for controlling supply of carbon dioxide from the compressor to the recuperator, wherein the first valve and the second valve are Opening is controlled according to the compressor inlet state to control the compressor inlet pressure.

Before supplying the carbon dioxide that has passed through the cooler to the compressor, a check valve for controlling the inflow of the second heater heating the carbon dioxide and the carbon dioxide discharged from the cooler into the compressor or into the second heater is provided. Includes.

It includes a vent portion for reducing the pressure by venting the carbon dioxide of the compressor.

Carbon dioxide vented by the vent unit may be stored, or may include an inventory tank in which carbon dioxide for injecting carbon dioxide into the circulation pipe is stored.

In a carbon dioxide power generation system that repeats the process of compression, heating, expansion, and cooling while passing through a compressor, a recuperator, a first heater, a turbine, a recuperator, and a cooler, preventing the compressor inlet operating point from entering the steam dome when the compressor starts To determine whether the inlet state of the compressor is in a gas state, and as a result of determination, if the compressor inlet state is a gas state, perform step 1 of driving the compressor. If the inlet state of the compressor is not a gas state, the compressor inlet state is TS. After making the liquid state (1) in the diagram, two steps of driving the compressor are performed.

In the first step, the second valve for supplying the carbon dioxide of the compressor to the recuperator is closed, the compressor is driven while the first valve for recycling carbon dioxide of the compressor to the cooler is opened, and the compressor inlet The cooler is controlled such that the state is from a gaseous state (2) to a supercritical state (3).

When the compressor inlet state reaches the supercritical state (3), the second valve is opened and the first valve is closed while venting or injecting carbon dioxide so that the compressor inlet state is a gaseous state in the supercritical state (3). (4) is controlled, and the carbon dioxide discharged from the compressor is heated by the recuperator and the first heater in the process of the compressor inlet state being from the supercritical state (3) to the gas state (4) and supplied to the turbine. .

The second step vents the carbon dioxide of the compressor to make the compressor inlet state into a liquid state (1).

In the second step, when the compressor inlet state is made into a liquid state (1), a second valve for supplying carbon dioxide of the compressor to the recuperator is closed, and a first valve for recycling carbon dioxide of the compressor to the cooler To open, drive the compressor, control the cooler such that the compressor inlet state is from a gas state (2) to a supercritical state (3), and inject carbon dioxide into the carbon dioxide power generation system.

When the compressor inlet state reaches the supercritical state (3), the second valve is opened and the first valve is closed while venting or injecting carbon dioxide so that the compressor inlet state is a gaseous state in the supercritical state (3). (4) is controlled, and the carbon dioxide discharged from the compressor is heated by the recuperator and the first heater in the process of the compressor inlet state being from the supercritical state (3) to the gas state (4) and supplied to the turbine. .

In a carbon dioxide power generation system that repeats the process of compression, heating, expansion, and cooling while passing through a compressor, a recuperator, a first heater, a turbine, a recuperator, and a cooler, carbon dioxide discharged at the start of the compressor or from the cooler to the compressor Carbon dioxide is heated in a second heater before supplying such that the compressor inlet state is in a gaseous state (2) or a supercritical state (3).

The check valve shuts off the carbon dioxide discharged from the cooler directly into the compressor, so that the carbon dioxide discharged from the cooler is started or when the compressor starts to flow into the compressor.

The present invention uses a compressor and lowers the compressor inlet operating point to 1'below the critical point so that the operating point does not pass through the steam dome to make it liquid, and the carbon dioxide generation cycle is 1'-2'-3-4-5-6- in the TS diagram. There is an effect to increase the efficiency of the cycle by driving so that 1'is repeated.

In addition, the present invention has an effect that can prevent the compressor damage by driving the compressor in the outer region of the steam dome to the compressor inlet state by venting the system to reduce the pressure when the compressor starts.

In addition, the present invention has the effect of heating the carbon dioxide at the start of the compressor to make the compressor inlet state into a gaseous state or a supercritical state, and driving the compressor to prevent compressor damage and to operate the system more efficiently.

1 is a diagram showing a typical supercritical carbon dioxide brater cycle and a modified carbon dioxide power generation cycle according to an embodiment of the present invention.
Figure 2 is a block diagram showing a supercritical carbon dioxide power generation system according to an embodiment of the present invention.
Figure 3 is a TS diagram showing the compressor starting sequence according to an embodiment of the present invention.
Figure 4 is a flow chart for explaining the starting method of the supercritical carbon dioxide power generation system according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

For convenience of description, a configuration example of a supercritical carbon dioxide power generation system will be described first with reference to FIG. 2.

2, the supercritical carbon dioxide power generation system 100 of the present invention includes a compressor 110, a recuperator 120, a first heater 130, a turbine 140, and a cooler 150 connected by circulation pipes. ). The circulation pipe is a pipe that constitutes a closed loop through which carbon dioxide circulates to form a carbon dioxide power generation cycle.

The supercritical carbon dioxide power generation cycle applies a modified Brayton cycle that repeats the 1'-2'-3-4-5-6-1' process in the T-S diagram of FIG. 1 to improve efficiency.

Specifically, compression (1'→2') is performed in the compressor 110 of FIG. 2, and heating (2'→3→4) is performed while passing through the recuperator 120 and the first heater 130. , Turbine 140 while the process of expansion (4→5) is performed, cooling (5→6→1') is performed while passing through the recuperator 120 and the cooler 150, and the turbine 140 ). That is, the compressor 140 is heated at a high temperature by compressing carbon dioxide compressed under a critical condition or higher to drive the turbine 140.

This supercritical carbon dioxide power generation system is in the spotlight as a next generation power generation method with high efficiency and small size. In particular, a wide range of applications are possible because the temperature range of available heat sources is wide from high temperatures such as nuclear power generation to low temperatures such as engine exhaust gas. However, since the power generation efficiency is relatively low at a low temperature, a method of increasing efficiency by selecting a method of pressurizing the liquid with a pump by lowering the minimum temperature of the cycle as much as possible is preferred. However, in this case, the coolant temperature of the cooler is very important. In particular, when the air-cooled cooler is used, when the air temperature is high, the carbon dioxide exceeds the critical temperature, so that the liquid carbon dioxide at the pump inlet is converted to supercritical carbon dioxide. If the fluid cannot maintain the liquid phase at the pump inlet, the efficiency of the pump will drop sharply. In the case of using a water-cooled cooler, a cooling system for lowering the coolant temperature must be provided separately to avoid this phenomenon.

Therefore, the present invention compresses carbon dioxide using a compressor 110 instead of a pump.

Compress the liquid carbon dioxide using the compressor 110 instead of the pump, but reduce the compressor inlet temperature (operating point 1) below the critical point (operating point 1') to make it a liquid phase so that the operating point does not pass under the steam dome. Increase. Since this cycle is still located on top of the saturation dome, it is different from the Rankine Cycle despite compressing liquid carbon dioxide.

In the T-S diagram of FIG. 1, the liquid carbon dioxide at the operating point 1'is compressed by the compressor 110 of FIG. 2 to become a supercritical state of 2', and after heating in the recuperator 120, it becomes a state of 3. And after the final heating in the state of 4 in the first heater 130, the turbine 140 expands to the state of 5 to generate power. After that, it is cooled in the recuperator 120, passed through a state of 6, and then cooled in a cooler to become 1'liquid carbon dioxide in an initial state.

The compressor 110 compresses liquid carbon dioxide, the recuperator 120 heats the compressed supercritical carbon dioxide in the compressor through heat exchange, and the first heater 130 is primarily heated in the recuperator 120 The carbon dioxide is finally heated to make it in a high temperature and high pressure state, and the turbine 140 expands carbon dioxide in the high temperature and high pressure state heated by the first heater 130 to produce power. The recuperator 120 heat exchanges carbon dioxide past the turbine 140 and carbon dioxide past the compressor 110, thereby preheating the carbon dioxide past the compressor 110 and cooling the carbon dioxide past the turbine 140. The cooler 150 cools the carbon dioxide introduced through the recuperator 120 to make liquid carbon dioxide in an initial state.

The supercritical carbon dioxide system 100 includes a first valve 180 that controls recirculation of the carbon dioxide from the compressor 110 to the cooler 150 and a second valve that controls the supply of the carbon dioxide from the compressor 110 to the recuperator 120. It includes a valve 190. The first valve 180 and the second valve 190 are controlled to open and close according to the compressor inlet state to control the compressor inlet pressure.

Before supplying the carbon dioxide that has passed through the cooler 150 to the compressor, the second heater 170 heating the carbon dioxide and the carbon dioxide discharged from the cooler 150 into the compressor 110 or into the second heater 170. It includes a check valve 160 for controlling the inflow.

It includes a vent 210 for venting (discharging) carbon dioxide from the compressor 110 to reduce pressure. The vent portion 210 is used for the purpose of preventing the increase in pressure and the role of protecting the equipment through decompression and the role of decompressing the outlet pressure of the compressor 110 when the first valve 180 fails.

It includes an inventory tank (230) in which the carbon dioxide vented by the vent unit 210 is stored or carbon dioxide for injecting carbon dioxide into the circulation pipe is stored. The inventory tank 230 connects the discharge pipe and the injection pipe to the circulation pipe to discharge carbon dioxide from the circulation pipe or to inject carbon dioxide into the circulation pipe.

Carbon dioxide may be injected into the circulation pipe using the pump 220 connected to the inventory tank 230, or carbon dioxide may be injected into the circulation pipe by a pressure difference from a high pressure vessel including a tank lorry.

2 is a schematic view for explaining the carbon dioxide power generation cycle of the present invention, reveals that the present invention is not limited to this configuration.

In the carbon dioxide power generation cycle of the present invention, a phase change occurs from a liquid phase to a supercritical phase, but since the density change is not large, stable compressor operation is possible.

Just as both air-cooled or water-cooled coolers can be used to make the pump inlet condition in the liquid phase in the pumped carbon dioxide power system, the air-cooled or water-cooled coolers for condensing carbon dioxide in the cooling (6→1') process are also used. All can be used. However, an important difference from a carbon dioxide power system using a pump is that in the case of a carbon dioxide power system using a compressor, if the temperature of the refrigerant is not sufficiently low, the minimum temperature of the cycle is sufficiently increased to increase the operating point (1-2-3-4- By changing to 5-6-1), it is possible to operate smoothly even at a new driving point. As described above, when the inlet condition of the compressor is set to a supercritical state, various problems such as efficiency reduction and shortening of life may occur when using the pump, but such a problem does not occur when the compressor is used.

It does not matter that the liquid phase and the supercritical phase coexist in the compressor 110, and it does not matter that the gas phase and the supercritical phase coexist. However, it is a problem that the gas phase and the liquid phase coexist in the compressor 110. If the operating point of the compressor enters the steam dome and the gas phase and liquid phase coexist, the compressor may be damaged.

Under normal operating conditions, it is unlikely that the gas phase and the liquid phase will coexist in the compressor, but when the compressor starts, the temperature and pressure of the carbon dioxide power generation system are low. It is likely to be in equilibrium. In this case, if the carbon dioxide is compressed immediately, there is a possibility of compressor damage.

Therefore, a method of starting a supercritical carbon dioxide power generation system is proposed to prevent compressor damage by preventing the compressor inlet from entering the steam dome.

As shown in FIG. 4, a method of starting a supercritical carbon dioxide power generation system that prevents compressor damage, first determines whether a compressor inlet state is a gas state when the system is stopped.

As a result of the determination before starting the compressor, if the compressor inlet state is a gas state, step 1 of driving the compressor 110 is performed. When the compressor inlet state is a gas state, it means that the gas phase and the liquid phase do not coexist, so the compressor is driven.

In the first step, the second valve 190 for supplying carbon dioxide from the compressor 110 to the recuperator 120 is closed, and the first valve 180 for recirculating carbon dioxide from the compressor 110 to the cooler 150 is provided. In the open state, the operation of the compressor 110 is started.

When the compressor 110 starts and operates, the compressor outlet temperature and the outlet pressure increase. Before the start of the operation of the compressor 110, the second valve 190 is closed and the first valve 180 is opened. At this time, the inlet pressure of the compressor can be controlled by being designed so that sufficient decompression can be achieved at the first valve 180. .

The cooler 150 is controlled such that the compressor inlet state is from the gas state 2 to the supercritical state 3. The cooler 150 controls the compressor inlet temperature to be maintained above the critical temperature, so that the compressor inlet state passes through the gas state 2 to become the supercritical state 3.

The pressure in the supercritical state 3 should be operated at a state higher than the critical pressure of carbon dioxide (7.3733 MPa). When the compressor inlet state reaches the supercritical state (3), the second valve 190 is slowly opened, and the first valve 180 is gradually closed while venting or injecting carbon dioxide to inject the compressor into a supercritical state (3 ) To control the gas state (4).

In the process of the compressor inlet state from the supercritical state (3) to the gaseous state (4), the carbon dioxide discharged from the compressor 110 is heated through the recuperator 120 and the first heater 130 and the turbine 140 Supply to allow the turbine 140 to produce power. When the second valve 190 is sufficiently opened, the heat source is completely applied, and the compressor inlet temperature and pressure reach a steady state, the start-up process is completed.

On the other hand, as a result of determination before starting the compressor, if the compressor inlet state is not in the gas state, the compressor inlet state is made in the liquid state 1 in the T-S diagram of FIG. 3 and then the second step of driving the compressor 110 is performed.

The second step vents the carbon dioxide of the compressor 110 to make the compressor inlet state into a liquid state (1). If the compressor inlet state is not in a gaseous state, it is highly likely that the compressor inlet is in equilibrium with the state inside the steam dome, as shown in state (0) of FIG. 3. In this case, when the carbon dioxide is directly compressed, since there is a possibility of damage to the compressor 110, the system is vented and depressurized to make the state of FIG. 3 (1), and then the compressor 110 starts to operate.

The vented carbon dioxide may be stored in the inventory tank 230 shown in FIG. 2 or a storage device equivalent thereto and reused, or discharged to the atmosphere or other safe areas for disposal.

When the compressor inlet state is liquid (1), the second valve 190 for supplying the carbon dioxide of the compressor 110 to the recuperator 120 is closed, and the carbon dioxide of the compressor 110 is recirculated to the cooler 150 The first valve 180 for opening is opened, and the compressor 110 is driven.

When the compressor 110 starts to operate, the compressor outlet temperature and outlet pressure increase. When the compressor 110 is driven, the second valve 190 is closed and the first valve 180 is opened. The inlet pressure of the compressor can be controlled by being designed so that sufficient decompression can be achieved at the first valve 180.

The cooler 150 is controlled to inject carbon dioxide into the system so that the compressor inlet state is from the gas state 2 to the supercritical state 3. Here, the system is to inject carbon dioxide into the circulation pipe. If a vent of carbon dioxide is needed when the compressor is started, carbon dioxide is injected into the system.

The higher the pressure of the supercritical state 3 is, the higher the critical pressure of carbon dioxide (7.3733 MPa) is. Carbon dioxide is injected into the circulation pipe located between the cooler 150 and the recuperator 120.

When the compressor inlet state reaches the supercritical state (3), the second valve 190 is slowly opened, and the first valve 180 is gradually closed while venting or injecting carbon dioxide to finally bring the compressor inlet state to a supercritical state. In (3), it is controlled to become the gas state (4).

In the process of the compressor inlet state from the supercritical state (3) to the gaseous state (4), the carbon dioxide discharged from the compressor 110 is heated through the recuperator 120 and the first heater 130 and the turbine 140 Supply to allow the turbine 140 to produce power. When the second valve 190 is sufficiently open, the heat source of the first heater 130 is applied, the turbine 140 produces power and the compressor inlet temperature and pressure reach a steady state, the start-up process is completed.

Here, the application of the heat source means that the first heater 130 starts supplying heat to the loop before going from 3 to 4 in FIG. 1. When heat is supplied to the loop, the turbine 140 starts to output, and after the work required for the compressor 110 gradually increases to 0, power is subsequently generated. Since the compressor inlet temperature in FIG. 1 is controlled by the cooler 150, the compressor inlet temperature does not increase in applying a heat source to the first heater 130. When it is controlled to change from 3 to 4 by the application of the heat source of the first heater 130, the cooler 150 increases the amount of cooling so that the compressor inlet temperature decreases.

On the other hand, when starting the compressor or before supplying the carbon dioxide that has passed through the cooler 150 to the compressor 110, the carbon dioxide is heated in the second heater 170 so that the inlet state of the compressor is a gas state (2) or a supercritical state (3). Can be.

In this case, the check valve 160 blocks that the carbon dioxide discharged from the cooler 150 flows directly into the compressor 110, so that the carbon dioxide discharged from the cooler 150 or when the compressor starts is blocked by the second heater 170. After that, it can be introduced into the compressor 110.

For example, when starting the compressor, by heating carbon dioxide, the compressor inlet state omits the liquid state (1) from the state (0) of FIG. 3 and goes directly to the gas state (2) or supercritical state (3). It is possible. In this case, since carbon dioxide is not vented when the compressor is started, it is not necessary to inject additional carbon dioxide. The type of the second heater is not limited to a specific type, and a plurality of heaters (Aux. Heaters) may be used and is not limited to a specific location.

The above-described starting method of the supercritical carbon dioxide power generation system to prevent damage to the compressor is applied when the compressor is started while the compressor is stopped, the compressor is started, and compression (1'→2') and heating (2'→3 of FIG. 1) are performed. →4), expansion (4→5), cooling (5→6→1') After the process is performed once, the existing general options may be applied in a normal operation situation.

The above-described supercritical carbon dioxide power generation system and its starting method can use both air-cooled or water-cooled coolers using a compressor, and lower the compressor inlet operating point to 1'below the critical point so that the operating point does not pass under the steam dome to make it liquid. The efficiency of the cycle can be increased by operating the carbon dioxide power generation cycle such that 1'-2'-3-4-5-6-1' is repeated in the TS diagram.

In addition, when the compressor is started, the system may be vented and depressurized to make the compressor inlet state into a liquid state and drive the compressor to prevent compressor damage.

In addition, when the compressor is started, carbon dioxide is heated to make the compressor inlet state into a gaseous state or a supercritical state, and the compressor is driven to prevent damage to the compressor.

The above-described method prevents the compressor inlet operating point from entering the steam dome when the compressor starts, thereby increasing the efficiency of the carbon dioxide power generation cycle while preventing compressor damage.

As described above, the supercritical carbon dioxide power generation system is compressed (1'→2'), heated (2'→3→4), expanded (4→5), and cooled (5→6→1') in FIG. It can be configured to repeat to increase the efficiency of the cycle. However, if the temperature of the refrigerant is not sufficiently low, the minimum temperature of the cycle is sufficiently increased to compress the operating point in FIG. 1 (1→2), heating (2→3→4), expansion (4→5), cooling (5→). 6→1').

The present invention has been described with the best embodiments in the drawings and specifications. Here, although specific terms have been used, they are used for the purpose of describing the present invention only, and are not used to limit the scope of the present invention described in the meaning limitation or the claims. Therefore, the present invention will be understood by those skilled in the art that various modifications and other equivalent embodiments are possible. Therefore, the true technical scope of the present invention should be defined by the technical spirit of the appended claims.

100: supercritical carbon dioxide power generation system
110: compressor 120: recuperator
130: first heater 140: turbine
150: cooler 160: check valve
170: second heater 180: first valve
190: second valve 210: vent portion
220: pump 230: inventory tank

Claims (13)

A circulation pipe through which carbon dioxide circulates;
A compressor that compresses liquid carbon dioxide at the operating point 1'of the TS diagram circulating through the circulation pipe to become a supercritical state (2');
A recuperator for heating the carbon dioxide compressed in the compressor through heat exchange;
A first heater for heating carbon dioxide heated in the recuperator;
A turbine for generating power by introducing and expanding carbon dioxide heated in the first heater; And
A cooler that cools the carbon dioxide discharged from the turbine and flows through the recuperator to become the 1'liquid carbon dioxide;
Supercritical carbon dioxide power generation system comprising a. The method according to claim 1,
A first valve for controlling recirculation of carbon dioxide from the compressor to the cooler; And
A second valve for controlling the supply of carbon dioxide from the compressor to the recuperator;
It includes,
The first valve and the second valve is supercritical carbon dioxide power generation system, characterized in that the opening is controlled according to the compressor inlet state to control the compressor inlet pressure. The method according to claim 1,
Before supplying the carbon dioxide that has passed through the cooler to the compressor,
A second heater for heating the carbon dioxide; And
A check valve for controlling inflow of carbon dioxide discharged from the cooler into the compressor or inflow into the second heater;
Supercritical carbon dioxide power generation system comprising a. The method according to claim 1,
Supercritical carbon dioxide power generation system comprising a vent portion for reducing the pressure by venting the carbon dioxide of the compressor. The method according to claim 4,
Carbon dioxide vented by the vent portion is stored, or
A supercritical carbon dioxide power generation system comprising an inventory tank in which carbon dioxide is stored for injecting carbon dioxide into the circulation pipe. In the carbon dioxide power generation system repeating the process of compression, heating, expansion, and cooling while passing through a compressor, a recuperator, a first heater, a turbine, a recuperator, and a cooler,
When starting the compressor, prevent the compressor inlet from entering the steam dome.
It is determined whether the compressor inlet state is a gas state,
As a result of the determination, if the inlet state of the compressor is a gaseous state, a first step of driving the compressor is performed,
If the compressor inlet state is not in the gaseous state, starting the supercritical carbon dioxide power generation system, characterized in that the step of driving the compressor after making the compressor inlet state into the liquid state (1) in the TS diagram. The method according to claim 6,
Step 1 above
The second valve for supplying the carbon dioxide of the compressor to the recuperator is closed, and the compressor is started while the first valve for recycling carbon dioxide of the compressor to the cooler is opened,
A method of starting a supercritical carbon dioxide power generation system, characterized in that the cooler is controlled such that the compressor inlet state is in a gaseous state (2) to a supercritical state (3). The method according to claim 7,
When the compressor inlet state reaches the supercritical state (3),
The second valve is opened and the first valve is closed to vent or inject carbon dioxide to control the compressor inlet state from a supercritical state (3) to a gaseous state (4),
Supercritical carbon dioxide power generation, characterized in that carbon dioxide discharged from the compressor is heated through a recuperator and a first heater and supplied to a turbine in the process where the compressor inlet state becomes a supercritical state (3) to a gaseous state (4). How to start the system. The method according to claim 6,
Step 2 above
A method of starting a supercritical carbon dioxide power generation system, characterized by venting carbon dioxide of the compressor to make the inlet state of the compressor liquid (1). The method according to claim 9,
Step 2 above
In the compressor inlet state is liquid (1),
The second valve for supplying the carbon dioxide of the compressor to the recuperator is closed, the first valve for recirculating the carbon dioxide of the compressor to the cooler is opened, and the compressor is started,
A method of starting a supercritical carbon dioxide power generation system, characterized in that the cooler is controlled to inject the carbon dioxide into the carbon dioxide power generation system so that the compressor inlet state becomes a supercritical state (3) in a gas state (2). The method according to claim 10,
When the compressor inlet state reaches the supercritical state (3),
The second valve is opened and the first valve is closed to vent or inject carbon dioxide to control the compressor inlet state from a supercritical state (3) to a gaseous state (4),
Supercritical carbon dioxide power generation, characterized in that carbon dioxide discharged from the compressor is heated through a recuperator and a first heater and supplied to a turbine in the process where the compressor inlet state becomes a supercritical state (3) to a gaseous state (4). How to start the system. In the carbon dioxide power generation system repeating the process of compression, heating, expansion, and cooling while passing through a compressor, a recuperator, a first heater, a turbine, a recuperator, and a cooler,
When starting the compressor or before supplying carbon dioxide discharged from the cooler to the compressor, carbon dioxide is heated in a second heater so that the compressor inlet state becomes a gas state (2) or a supercritical state (3). How to start a supercritical carbon dioxide power generation system. The method according to claim 12,
Supercritical, characterized in that the check valve shuts off the carbon dioxide discharged from the cooler directly into the compressor, so that the carbon dioxide discharged from the cooler or when the compressor starts up is introduced into the compressor through the second heater. How to start the carbon dioxide power generation system.

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